Filtration pump for a swimming pool

ABSTRACT

Disclosed is a filtration pump for a swimming pool, including a pump body suitable for resting on a horizontal support, the pump body has a suction port extended by a cylindrical suction structure with a horizontal axis, and a discharge port, extended by a cylindrical discharge structure with a vertical axis. The pump body allows adjustment:
         of the dimension corresponding to the height of the horizontal axis of the cylindrical suction structure, relative to the support,   of the dimension corresponding to the height of the horizontal plane of the free end of the cylindrical discharge structure relative to the support, and   of the dimension corresponding to the distance separating the vertical plane of the free end of the cylindrical suction structure and the vertical axis of the cylindrical discharge structure,
 
and this continuously, each over a range of values and regardless of the others.

TECHNICAL FIELD THAT THE INVENTION IS RELATED TO

The present invention concerns the general field of swimming poolequipment; it particularly concerns the filtration pumps for swimmingpools.

TECHNOLOGICAL BACKGROUND

Recycling the water of a swimming pool, especially for the purpose ofits filtration, is done by means of electric pumps.

These filtration pumps comprise a pump body associated with an electricmotor provided with a paddle wheel. This pump body is provided with asuction port which comprises means for allowing it to be coupled to asuction coupling of a water inlet piping and with a discharge port whichcomprises means for allowing it to be coupled to a discharge coupling ofa water outlet piping. The water circuit between the swimming pool andthe pump comprises a filtering installation, for example of thesandbox-filter type.

There are numerous models of such pumps (cf. for example EP-2 113 705 orEP-0 544 610), but in a very general manner, their body comprises a basefor positioning it and for fixing it on a dedicated flat horizontalsupport; the axis of their suction port is horizontal and provided atthe front side of the pump body facing a lodging space for apre-filtering system (traditionally a removable basket constituting apre-filter), and their discharge port is provided on top of the pumpbody with its axis being vertical.

The horizontal axis of the suction port and the vertical axis of thedischarge port extend generally in the same vertical plane(corresponding to the median vertical plane of the pump body).

The differences between the pump models existing on the market lieespecially in the types of means for connection to the suction couplingand to the discharge coupling of the inlet piping and outlet piping, aswell as in the positioning dimensions of the suction port and of thedischarge port, i.e.

-   -   the height dimension of the axis of the suction port,    -   the height dimension of the horizontal plane of the discharge        port, and    -   the length/distance dimension between the axis of the discharge        port and the vertical plane of the suction port;        these different dimensions of positioning being liable to vary        by some millimeters or some centimeters from one pump model to        another.

During a first installation, the installer constructs the piping plantaking into account the chosen pump model.

Then, when it is necessary to change the pump, the operator has to dothat change with an identical pump; or, when he uses a different pumpmodel, he has to modify the positioning of the suction coupling and thedischarge coupling of the water inlet piping and the water outletpiping, which causes supplemental cost of time and of material.

OBJECT OF THE INVENTION

The present invention aims at overcoming these disadvantages bysuggesting a very versatile pump structure suitable for being configuredfor being coupled in a simple and rapid manner to existing suction anddischarge couplings, whatever be a large part of the previously usedpump models.

To this end, that versatile filtration pump for a swimming pool is ofthe type comprising a pump body suitable for resting on a horizontalsupport, said pump body comprising a lodging space for a pre-filteringsystem, as well as means for receiving a motor, and it is provided with:

-   -   a suction port, said suction port being positioned facing the        lodging space for the pre-filtering system, and being extended        by a cylindrical suction structure with a horizontal axis, the        free end of which extends in a vertical plane P1 and is provided        with means for being coupled to a suction coupling, and    -   a discharge port, said discharge port being extended by a        cylindrical discharge structure with a vertical axis, the free        end of which extends in a horizontal plane P2 and is provided        with means for being coupled to a discharge coupling;

the horizontal axis of said cylindrical suction structure is intended toextend according to a height dimension C1 with respect to saidhorizontal support of said pump body;

the horizontal plane P2 of the free end of the cylindrical dischargestructure is intended to extend according to a height dimension C2 withrespect to said horizontal support; and the vertical plane P1 of thefree end of the cylindrical suction structure and the vertical axis ofsaid cylindrical discharge structure are separated by a length dimensionC3.

On the other hand, the axes of said cylindrical suction structure anddischarge structure are situated in the same vertical plane P3.

And according to the present invention, for obtaining the desiredversatility, the pump body comprises means allowing the adjustment ofsaid height dimension C1, means allowing the adjustment of said heightdimension C2, and means allowing the adjustment of said length dimensionC3, continuously, each over a range of values and regardless of theothers.

According to a preferred embodiment, the cylindrical discharge structurecomprises a cylindrical discharge coupling mounted with the possibilityof axial mobility through an annular gasket associated to said dischargeport, for allowing the adjustment of the afore-mentioned heightdimension C2.

The cylindrical discharge structure preferably comprises compressionmeans for compressing in a reversible manner said gasket between thecircumference of said discharge port and the outer surface of thecylindrical discharge coupling, in order to achieve simultaneously theaxial locking of said cylindrical discharge coupling and the tightness.

Still in this context, according to a specific form of embodiment, thedischarge port of the pump body extends to the outside by a cylindricaldischarge section provided with a tapping, the inner diameter of saidcylindrical discharge section being greater than the diameter of saiddischarge port for providing an inner shoulder oriented to the outside;further, the afore-mentioned compression means comprises a clamping nutintended to surround said cylindrical discharge coupling and providedwith an extension comprising an outer thread intended to cooperate withsaid tapping of the cylindrical discharge section in an appropriatemanner in order that its free end compresses directly or indirectly saidgasket against said inner shoulder and against the outer surface of saidcylindrical discharge coupling.

Preferably, a conical and open compression ring is located between saidgasket and an inclined surface formed in the inner surface of theclamping nut.

On the other hand, still in an advantageous manner, the cylindricaldischarge section of said discharge port is integrally formed, i.e. asone piece, with the pump body.

According to another special feature, the cylindrical suction structurecomprises a cylindrical suction coupling mounted with the possibility ofaxial mobility through an annular gasket associated to said suctionport, for allowing the adjustment of said afore-mentioned lengthdimension C3.

In this context, the cylindrical suction structure preferably comprisescompression means for compressing in a reversible manner said gasketbetween the circumference of said suction port and the outer surface ofsaid cylindrical suction coupling, in order to achieve simultaneouslythe axial locking of said cylindrical suction coupling and thetightness.

The suction port of the pump body preferably extends to the outside by acylindrical suction section provided with a tapping, the inner diameterof said cylindrical suction section being greater than the diameter ofsaid suction port for providing an inner shoulder oriented to theoutside. Further, said compression means comprises a clamping nutintended to surround said cylindrical suction coupling and provided withan extension comprising an outer thread intended to cooperate with saidtapping of the cylindrical suction section, in an appropriate manner inorder that its free end compresses, directly or indirectly, said gasketagainst said inner shoulder and against the outer surface of saidcylindrical suction coupling.

Still preferably, a conical and open compression ring is located betweensaid gasket and an inclined surface formed in the inner surface of saidclamping nut.

According to yet another specific feature, the suction port formed inthe pump body is designed oversized in relation to the diameter of saidcylindrical suction structure; on the other hand, the pump comprises anintermediate plate carrying said cylindrical suction structure, saidintermediate plate comprising holes for being fixed to the pump body bymeans of screws, said fixing holes having an elongate shape the majoraxis of which is oriented parallel to the plane P3 and to the axis ofthe cylindrical discharge structure, for allowing the adjustment of theafore-mentioned height dimension C1.

Said intermediate plate preferably comprises a suction port whichextends by said cylindrical suction section associated to saidcylindrical suction coupling and said compression means.

The cylindrical suction coupling and discharge coupling advantageouslycomprise a tapped end or a threaded end for being coupled respectivelyto the suction coupling and to the discharge coupling.

On the other hand, the cylindrical suction coupling and dischargecoupling preferably comprise a peripheral protruding structure having apolygonal cross-section for holding them during screwing and unscrewingoperations of the suction coupling and the discharge coupling, andoptionally of the associated clamping nuts.

The present invention will be further illustrated, without being limitedin any way, by the following description of a specific embodiment,merely given as an example and shown on the accompanying drawings, inwhich:

FIG. 1 is a perspective view of a filtration pump for a swimming pool,according to the invention, formed by a pump body associated to anelectric motor;

FIG. 2 is a front view of the pump body shown on FIG. 1;

FIG. 3 is a side view of the pump body of FIG. 2;

FIG. 4 is a cross-sectional view of the pump body along thecross-section plane 4-4 of FIG. 2;

FIG. 5 is an enlarged view of a part of FIG. 4, showing in detail thecoupling means of the discharge port to the discharge coupling;

FIG. 6 is an enlarged view of a part of FIG. 4, showing in detail themeans for coupling the suction port to the suction coupling;

FIG. 7 is an exploded perspective view of the means for coupling thesuction port to the suction coupling.

DETAILED DESCRIPTION OF AN EMBODIMENT

FIG. 1 illustrates in a perspective view a filtration pump 1 accordingto the invention, comprising a pump body 2 associated to an electricmotor 3 (shown by a dashed line), e.g. an asynchronous two-pole motor of1.1 kW. On FIGS. 2, 3, and 4, only the pump body 2 is shown.

That pump body 2 comprises a base 4 allowing it to be fixed on ahorizontal support S by means of screws.

It comprises an essentially cylindrical front structure 5 having avertical axis, being open at the upper part, and provided, at thatlevel, with a removable closing hood 6. That cylindrical front structure5 defines a lodging space 7 intended for receiving a not shownfiltration system forming a pre-filter for retaining certainwaste/debris from the swimming-pool water, in order to protect thepaddle wheel of the electric motor 3.

That cylindrical front structure 5 of the pump body 2 is extended by arear structure 8, likewise essentially cylindrical, having a horizontalaxis and defining the pumping chamber 9 as such, intended for receivingthe conical diffuser and the paddle wheel of the electric motor 3. Thatrear structure 8 is also adapted for allowing the electric motor 3 to befixed.

The cylindrical front and rear structures 5 and 8 of the pump body 2 arein fluid communication with each other by means of an inner opening 10.

The pump body 2 comprises a suction port 11 having a horizontal axis 12,which is formed in the cylindrical front structure 5 facing the lodgingspace 7 for the pre-filtering system; that suction port 11 extends by acylindrical suction structure 13 having a horizontal axis 13′, the freeend 14 of which is provided with means 15 for being coupled to a suctioncoupling RA. That suction coupling RA, simply shown on FIG. 1 by adashed line, is an integral part of the piping circuit between theswimming pool and the pump 1.

As can be seen on FIGS. 1 and 4, the free end 14 of that cylindricalsuction structure 13 extends in a vertical plane P1.

On the other hand, the height dimension of the horizontal axis 13′ ofthe cylindrical suction structure 13 with respect to the horizontalsupport S of the pump body 2 is referenced Cl on FIG. 4.

The pump body 2 further comprises a circular discharge port 16, having avertical axis 17, which is formed in the upper part of the rearstructure 8; that discharge port 16 extends by a cylindrical dischargestructure 18, having a vertical axis 18′, the free end 19 of which isprovided with means 20 for being coupled to a discharge coupling RF.

Here, the vertical axes 17 and 18′ are merged with one another.

As can be seen on FIGS. 1 and 4, the free end 19 of that cylindricaldischarge structure 18 extends in a horizontal plane P2; and thehorizontal plane P2 is situated at a height dimension C2 with respect tothe horizontal support S of the pump body 2 (FIG. 4).

On the other hand, still on FIG. 4, one remarks that the vertical planeP1 of the cylindrical suction structure 13 is separated from thevertical axis 18′ of the cylindrical discharge structure 18 by a lengthdimension C3.

Further, one also remarks that the horizontal axis 13′ of thecylindrical suction structure 13, and the axis 18′ of the cylindricaldischarge structure 18, are placed on the same vertical plane P3,corresponding to the median vertical plane of the pump body 2 (FIG. 2).

According to the invention, the pump body 2 comprises means describedhereafter in more details, which allows the adjustment of theafore-mentioned dimensions C1, C2, and C3, and that in a continuousmanner, each over a range of values and regardless of the others.

To that end, in the illustrated example, and as is shown in details onFIG. 5, the cylindrical discharge structure 18 comprises a cylindricaldischarge coupling 21 which is mounted with the possibility of axialmobility through an annular gasket 22 associated to the discharge port16.

That cylindrical discharge structure 18 is associated to compressionmeans 23 adapted for compressing the gasket 22 in a reversible manner,between the circumference of the discharge port 16 and the outer surfaceof the cylindrical discharge coupling 21, in order to producesimultaneously the axial locking of that cylindrical coupling 21 and thetightness.

More precisely, the discharge port 16 formed in the pump body 2 extendsto the outside by a cylindrical discharge section 24, formed here in asingle piece, which is provided with a tapping 25, and the innerdiameter of which is greater than the diameter of the discharge port 16,in order to obtain an inner shoulder 26 oriented to the outside.

Further, the afore-mentioned compression means 23 comprises a clampingnut 27 intended to surround the cylindrical discharge coupling 21 andprovided with an extension 28 comprising an outer thread 29 adapted forcooperating with the tapping 25 of the cylindrical discharge section 24in an adapted or appropriate manner, in order that its free endcompresses the gasket 22 against the afore-mentioned shoulder 26, andagainst the outer surface of the cylindrical discharge coupling 21, andthis by means of a conical clamping ring 30.

That conical ring 30, preferably of the “open” type (which means: notcontinuous), is independent from the clamping nut 27, and it isinterposed between the annular gasket 22 and an inclined surface 31formed in the inner surface of the clamping nut 27.

The outer diameter of the cylindrical discharge coupling 21 corresponds,except for the clearance, to the inner diameter of the clamping nut 27,of the clamping ring 30 before compression, of the annular gasket 22before compression, and of the port 16 formed in the wall of the pumpbody 2.

Thus, it is understood that before complete compression of the nut 27,the cylindrical discharge coupling 21 can slide axially along the axis18′, and this in a continuous manner, over a defined range of values,thanks to the cooperation of smooth surfaces sliding one over the other;and after having adjusted the desired height dimension C2 of thehorizontal plane P2 (especially as a function of the positioning of thedischarge coupling RF), this dimension C2 can be locked by the clampingnut 27.

During that clamping of the nut 27 on the cylindrical discharge section24, the tapping 25 cooperates with the thread 29. The extension 28 ofthe nut 27 pushes the conical ring 30 (by the inclined surface 31)towards the pump body 2, and the conical ring 30 compresses the gasket22 against the shoulder 26 and against the outer surface of thecylindrical coupling 21, in order to lock the position of the latter andto assure the tightness of the connection (the locking and the tightnessbeing achieved by the ring 30 and the gasket 22).

The open conical ring 30 allows to optimize the features of theclamping.

At the free end 19 of the cylindrical coupling 21, one remarks thepresence of the means 20 for the coupling to the discharge coupling RF,here as a tapping.

On the periphery of the outer face of the cylindrical discharge coupling21, one further remarks the presence of a protruding polygonal structure32 (in the present case: hexagonal), which allows to maintain saidcylindrical coupling (for example by means of a wrench or of pliers)during screwing and unscrewing operations of the nut 27 and thedischarge coupling RF. That protruding polygonal structure 32 is locatedon the side of the free end 19 of the cylindrical coupling 21.

On the other hand, at the front part 5 of the pump body 2, as shown indetails on FIGS. 6 and 7, the cylindrical suction structure 13 has astructure which is similar to that of the cylindrical dischargestructure 18, except for the fact that it comprises an intermediateplate 33 allowing it to be fixed on the pump body 2, that intermediateplate 33 being conceived for being adjustable in height (for allowing anadjustment of the height dimension C1), and the suction port 11 beingoversized with respect to the diameter of the cylindrical suctionstructure 13, again for allowing that adjustment of the height dimensionC1.

To this end, the suction port 11 formed in the pump body 2 is ofgenerally elongate shape, its major axis being oriented vertically,parallel to the axis 18′ of the cylindrical discharge structure 18, andin the median vertical plane P3 of the pump body 2.

As to the intermediate plate 33, it has a generally square orrectangular shape and it comprises elongate holes 34 allowing it to befixed on the outer surface of the front part 5 of the pump body 2,facing the suction port 11 and against a receiving location 35 formed tothat end.

That mounting of the intermediate plate 33 is done by means of screws 36which cooperate with tapped holes formed at that location 35 of the pumpbody 2, on the periphery of the suction port 11.

The major axis of the elongate holes 34 extends vertically, parallel tothe major axis of the suction port 11, in order to allow the desiredvertical adjustment of the intermediate plate 33, and this in acontinuous manner and over a range of values (corresponding to themobility range of the screws 36 along the elongate holes 34).

In a manner similar to the cylindrical discharge structure 18, thecylindrical suction structure 13 comprises a cylindrical suctioncoupling 37 which is mounted with the possibility of axial mobility(along the horizontal axis 13′) through an annular gasket 38 associatedto an opening 39 formed in the intermediate plate 33 (placedcorresponding to the suction port 11 and liable to be assimilated to thelatter).

The diameter of the opening 39 corresponds roughly to the inner diameterof the cylindrical suction coupling 37 as well as to the minor axis ofthe suction port 11.

Further, that cylindrical suction structure 13 is associated tocompression means 40 adapted for compressing the gasket 38 in areversible manner between the periphery of the suction port 11-39 andthe outer surface of the cylindrical suction coupling 37, in order toproduce simultaneously the axial locking of the cylindrical coupling 37et the tightness.

More precisely, the suction opening 39 formed in the intermediate plate33 extends, on the side of the outer face 33 a of said plate 33, by acylindrical suction section 41 which is provided with a tapping 42 andthe diameter of which is greater than the inner diameter of the opening39, in order to form an inner shoulder 43 oriented to the outside.

As to the compressions means 40, it comprises a clamping nut 44 intendedto surround the cylindrical suction coupling 37 and which is providedwith an extension 45 comprising an outer thread 46 adapted forcooperating with said tapping 42 of the cylindrical suction section 41,in an appropriate manner in order that its free end compresses thegasket 38 against the afore-mentioned shoulder 43 and against the outersurface of said cylindrical suction coupling 37, and this by means of aconical clamping ring 47.

That conical ring 47, preferably of the “open” type (i.e. notcontinuous), is independent from the clamping nut 44 and it isinterposed between the annular gasket 38 and an inclined surface 48formed in the inner surface of the nut 44.

The outer diameter of the cylindrical suction coupling 37 corresponds,except for the clearance, to the inner diameter of the clamping nut 44,of the clamping ring 47 before compression, of the annular gasket 38before compression, and of the opening 39 formed in the intermediateplate 33.

Thus, one understands that, before complete clamping of the nut 44, thecylindrical suction coupling 37 can slide axially along the axis 13′ andin a continuous manner, over a range of determined values, thanks to thecooperation of smooth surfaces sliding over one another; and afterhaving adjusted the desired distance dimension C3 of the vertical planeP1, that dimension C3 can be locked by clamping the nut 44.

During that clamping of the nut 44 on the cylindrical suction section37, the tapping 42 cooperates with the thread 46; the extension 45 ofthe nut 44 pushes the conical ring 47 (by the inclined surface 48)towards the pump body 2, and the conical ring 47 compresses the gasket38 against the shoulder 43 and against the outer surface of thecylindrical coupling 37, in order to lock the position of the latter andto ensure the tightness of the connection (the locking and the tightnessbeing achieved by the ring 47 and the gasket 38).

There again, the open conical ring 47 allows to optimize the features ofthe clamping.

At the free end 14 of the cylindrical suction coupling 37, one remarksthe presence of means 15 for the coupling of the suction coupling RA,here as a thread.

On the periphery of the outer face of the cylindrical suction coupling37, one remarks, here as well, the presence of a protruding polygonalstructure 49 (in the present case: hexagonal), which allows to maintainsaid cylindrical coupling 37 (for example by means of a wrench or ofpliers) during screwing and unscrewing operations of the nut 44 and thesuction coupling RA.

That protruding polygonal structure 49 is located on the side of thefree end 14 of the cylindrical suction coupling 37.

A gasket 50 assures the tightness of the mounting of the plate 33 on thelocation 35 of the pump body 2. That gasket 50 is placed in an adaptedgroove 51 formed at the rear face 33 b of the plate 33 (intended to beplaced facing the location 35 of the pump body 2).

The groove 51 and the gasket 50 extend over the periphery of the opening39.

According to a variant of the embodiment, that groove and the gasketwhich it receives, may be arranged at the location 35 of the pump body2.

One understands that the elongate holes 34 for mounting the intermediateplate 33 allow an adjustment of the height dimension Cl of the axis 13′of the cylindrical suction coupling 37.

Such a filtration pump 1 allows the adjustment of the dimensions C1, C2,and C3 independently from one another, and this in a continuous manner,and each over a range of values, what allows it to be installed onnumerous existing configurations of suction couplings RA and dischargecouplings RF.

The mounting of the ends of the suction coupling 37 and the dischargecoupling 21 (tapping or thread 15, 20) are adapted to the suctioncoupling RA and the discharge coupling RF as existing at the site.

The tappings or threads 15, 20 may, for example, be of the tapped 1½″ or2″ type, of the threaded 2¼″ or 2¾″ type, and so on.

Optionally, the commercialized pump 1 may be associated to a pluralityof types of suction couplings 37 and discharge couplings 21 to be usedaccording to the existing type of RA and RF coupling.

Several types of plates 33 with a different positioning of the opening39 may also be proposed, to be used according to the desired dimensionC1. That or those plates 33 may be designed for being pivoted by 180°,in order to increase the possibilities of adjustment.

As a variant, the cylindrical suction section 41 may be formedintegrally, i.e.in one piece, with the pump body 2, as well as thecylindrical discharge section 24. In this case, the cylindrical suctionstructure 13 does not comprise any intermediate plate 33. The adjustmentof the height dimension C1 can then be performed by height-adjustmentmeans of the pump body 2, for example by height-adjustable feet.

Still as a variant, the end of the clamping nuts 27 and 44 may beadapted for assuring the direct compression of the gaskets 22 and 38.

1-14. (cancelled)
 15. Filtration pump (1) for a swimming pool comprisinga pump body (2) suitable for resting on a horizontal support (S), saidpump body (2) comprising a lodging space (7) for a pre-filtering systemas well as means for receiving a motor (3), and is provided with asuction port (11, 39), said suction port (11, 39) being positionedfacing the lodging space (7) for the pre-filtering system, and beingextended by a cylindrical suction structure (13) with a horizontal axis(13′), the free end (14) of which extends in a vertical plane (P1) andis provided with means (15) for being coupled to a suction coupling(RA), and a discharge port (16), said discharge port (16) being extendedby a cylindrical discharge structure (18) with a vertical axis (18′),the free end (19) of which extends in a horizontal plane (P2) and isprovided with means (20) for being coupled to a discharge coupling (RF),the horizontal axis (13′) of said cylindrical suction structure (13)being intended to extend according to a height dimension (C1) withrespect to said horizontal support (S) of said pump body (2), saidhorizontal plane (P2) of the free end (19) of the cylindrical dischargestructure (18) being intended to extend according to a height dimension(C2) with respect to said horizontal support (S), said vertical plane(P1) of the free end (14) of the cylindrical suction structure (13) andsaid vertical axis (18′) of the cylindrical discharge structure (18)being separated by a length dimension (C3), and said axes (13′, 18′) ofsaid cylindrical suction structure and discharge structure (13, 18)being situated in the same vertical plane (P3), wherein said pump body(2) comprises means (11, 33, 34, 39) allowing the adjustment of saidheight dimension (C1), means (16, 18, 21, 22) allowing the adjustment ofsaid height dimension (C2), and means (11, 13, 37, 38, 39) allowing theadjustment of said length dimension (C3), continuously, each over arange of values and regardless of the others.
 16. Filtration pump (1)according to claim 15, wherein said cylindrical discharge structure (18)comprises a cylindrical discharge coupling (21) mounted with thepossibility of axial mobility through an annular gasket (22) associatedto said discharge port (16) for allowing the adjustment of the heightdimension (C2).
 17. Filtration pump (1) according to claim 16, whereinsaid cylindrical discharge structure (18) comprises compression means(23) for compressing in a reversible manner said gasket (22) between thecircumference of said discharge port (16) and the outer surface of saidcylindrical discharge coupling (21), in order to achieve simultaneouslythe axial locking of said cylindrical discharge coupling (21) and thetightness.
 18. Filtration pump (1) according to claim 17, wherein saiddischarge port (16) of the pump body (2) extends to the outside by acylindrical discharge section (24) provided with a tapping (25), theinner diameter of said cylindrical discharge section (24) being greaterthan the diameter of said discharge port (16) for providing an innershoulder (26) oriented to the outside, and wherein said compressionmeans (23) comprises a clamping nut (27) intended to surround saidcylindrical discharge coupling (21) and provided with an extension (28)comprising an outer thread (29) intended to cooperate with said tapping(25) of said cylindrical discharge section (24), in an appropriatemanner in order that its free end compresses directly or indirectly saidgasket (22) against said inner shoulder (26) and against the outersurface of said cylindrical discharge coupling (21).
 19. Filtration pump(1) according to claim 18, further comprising a conical and opencompression ring (30) located between said gasket (22) and an inclinedsurface (31) formed in the inner surface of said clamping nut (27). 20.Filtration pump (1) according to claim 18, wherein said cylindricaldischarge section (24) of the discharge port (16) is formed as one piecewith the pump body (2).
 21. Filtration pump (1) according to claim 15,wherein said cylindrical suction structure (13) comprises a cylindricalsuction coupling (37) mounted with the possibility of axial mobilitythrough an annular gasket (38) associated to said suction port (11, 39),for allowing the adjustment of said length dimension (C3). 22.Filtration pump (1) according to claim 21, wherein said cylindricalsuction structure (13) comprises compression means (40) for compressingin a reversible manner said gasket (38) between the circumference ofsaid suction port (11, 39) and the outer surface of said cylindricalsuction coupling (37) in order to achieve simultaneously the axiallocking of said cylindrical suction coupling (37) and the tightness. 23.Filtration pump (1) according to claim 22, wherein said suction port(11, 39) of the pump body (2) extends to the outside by a cylindricalsuction section (41) provided with a tapping (42), the inner diameter ofsaid cylindrical suction section (41) being greater than the diameter ofsaid suction port (11, 39) for providing an inner shoulder (43) orientedto the outside, and wherein said compression means (40) comprises aclamping nut (44) intended to surround said cylindrical suction coupling(37) and provided with an extension (45) comprising an outer thread (46)intended to cooperate with said tapping (42) of said cylindrical suctionsection (41), in an appropriate manner in order that its free endcompresses, directly or indirectly, said gasket (38) against said innershoulder (43) and against the outer surface of said cylindrical suctioncoupling (37).
 24. Filtration pump (1) according to claim 23, furthercomprising a conical and open compression ring (47) located between saidgasket (38) and an inclined surface (48) formed in the inner surface ofsaid clamping nut (44).
 25. Filtration pump (1) according to claim 15,further comprising a suction port (11) formed in the pump body (2),being oversized in relation to the diameter of said cylindrical suctionstructure (13), and an intermediate plate (33), carrying saidcylindrical suction structure (13), said intermediate plate (33)comprising holes (34) for being fixed to the pump body (2) by means ofscrews (36), said fixing holes (34) having an elongate shape the majoraxis of which is oriented parallel to said plane (P3) et to said axis(18′) of the cylindrical discharge structure (18), for allowing theadjustment of said height dimension (C1).
 26. Filtration pump (1)according to claims 23, further comprising a suction port (11) formed inthe pump body (2), being oversized in relation to the diameter of saidcylindrical suction structure (13), and an intermediate plate (33),carrying said cylindrical suction structure (13), said intermediateplate (33) comprising holes (34) for being fixed to the pump body (2) bymeans of screws (36), said fixing holes (34) having an elongate shapethe major axis of which is oriented parallel to said plane (P3) et tosaid axis (18′) of the cylindrical discharge structure (18), forallowing the adjustment of said height dimension (C1); wherein saidintermediate plate (33) comprises a suction port (39) which extends bysaid cylindrical suction section (41) associated to said cylindricalsuction coupling (37) and said compression means (40).
 27. Filtrationpump (1) according to claim 15, wherein said cylindrical suctioncoupling (37) and discharge coupling (21) comprise a tapped end (20) ora threaded end (15) for being coupled respectively to the suctioncoupling (RA) and to the discharge coupling (RF).
 28. Filtration pump(1) according to claim 15, wherein said cylindrical suction coupling(37) and discharge coupling (21) comprise a peripheral protrudingstructure (32, 49) having a polygonal cross-section, for holding themduring screwing and unscrewing operations of the suction coupling (RA)and the discharge coupling (RF).
 29. Filtration pump (1) according toclaim 19, wherein said cylindrical discharge section (24) of thedischarge port (16) is formed as one piece with the pump body (2). 30.Filtration pump (1) according to claim 28, wherein said peripheralprotruding structure also holds the cylindrical suction coupling and thedischarge coupling during screwing and unscrewing operations of of theassociated clamping nuts (24, 44).